Product of all Subarrays of an Array

Given an array of integers arr of size N, the task is to print products of all subarrays of the array.

Examples:

Input: arr[] = {2, 4} 
Output: 64 
Here, subarrays are [2], [2, 4], [4] 
Products are 2, 8, 4 
Product of all Subarrays = 64

Input : arr[] = {10, 3, 7} 
Output : 27783000 
Here, subarrays are [10], [10, 3], [10, 3, 7], [3], [3, 7], [7] 
Products are 10, 30, 210, 3, 21, 7 
Product of all Subarrays = 27783000  

Naive Approach: A simple solution is to generate all sub-array and compute their product. 

27783000

Time Complexity: O(n³)

Auxiliary Space: O(1)

Efficient Approach: An efficient approach is to use two loops and calculate the products while traversing the subarrays.
Below is the implementation of the above approach:  

27783000

Time Complexity: O(n²)

Auxiliary Space: O(1)